Differential stage lift flow device, diaphragm type



Jan. 5, 1943. A, BOYNTON 2,307,016

DIFFERENTIAL STAGE LIFT FLOW DEVCE, DIAPHRAGM TYPE Filed Dec. a'. 1939 l.A from/frs.

A15/@auw Patented Jan. 5, 1943 UNi'iD STATES PATENT OFFICE DIFFERENTIALSTAGE LIFT FLOW DEVICE, DIAPHRAGM TYPE Alexander Boynton, San Antonio,Tex.

lApplication December 8, 1939, Serial No. 308,312.v 6 claims. (o1.13min) My invention relates to flowing devices for cased wells.

The principal object is to startl wells at comparatively low pressuresandv to cause them to flow through either the tubing or the casing at`low gas-oil ratios by employing similar means for flowing either way.

Other objects are: (l) to cause .the valve to seat with comparativelygreat force; (2) to automatically control the admission of pressureiiuid .to the load in proportion to the work required;

(3) to avoid the'use of 'all sliding contacts; and (4) toemploy'mechanism of extremely few parts, simple vin design andinexpensive to manufacture. These objects are attained by interposing adiaphragm with a valve yattached to it, between the pressure fluid andthe upstanding liquid column in the eduction tube. The valve has anopening extending through it and the diaphragm and is adapted to allowpassage of pressure fluid into. the well liquid in the eduction tube atlow differentifals and to cut off such iiow at higher differentials.

The foregoing will clearly appear from mechanism illustrated in theaccompanying drawing, in which:

Fig. 1 is an installationv plan of the -devices in awell.

Fig. 2 is a perspective view of the preferred embodiment of theinvention for tubing flow. (Svi) Fig. 3 is a longitudinal section of thedevice of the invention illustrated in Figs. 2 and 3.

Fig. 5 is a partial vertical section of the devicef shown in Fig. 4.

Similar referencecharacters are employed -to designate similar partsthroughout the several In Figs. 2 and'3, the tubular body I2, havingglf)The column of well liquid 'caused to stand upi) in the eduction tubeabove the liquid level in the induction tube will be referred to as theupstanding column.

The induction tube will be 4considered as the one having its innersurface in contact with the '5 vvaried to meet-diierent well conditions.

pressure fluid, -and the eduction tube will be considered to be the onehaving itsV inner surface in contact with the well liquid.

The annularly corrugated diaphragm l0., having the circular ange I4atting closely over the tubular boss I2d. is hermetically secured betweenthis boss and the packing I8 by the cap I3, having threaded engagementover the boss I2d which boss is centrally disposed between the guidefins 2c. Theidiameter of Athis diaphragm may be such as two inches. Thecircular Vplate I5, having slight clearance within the chamberiZh.- issecured to the flat central portion of the diaphragm by means .of thethreaded engagement between this plate and the screw I6. The diaphragmand the plate l5 are urged against the Icap I3 by the force of the'sprngI'I installed-under some compression between the plate I5 and the floorof the bore |211I within which bore the spring has slight clearance. Theopening I3a, central of thecap I3, is aligned with the extension havingthe valve I5a formed upon its-end, and is adapted to receive the head ofthe screw I6, as appears in Fig.V 3. The purpose of the plate I5 is torestrain the diaphragm and thus prevent it from rupture during highdiiierentials.

The tubular valve I 5a, which may have a diameter such as to 1/2 inch,is adapted to closefupcn .the seat.A I2f, and is positioned central ofthe tapered bore I2g. The extension formed into the valve I5a, in theopen position of the valve as shown in Fig. 3, has impaired clearancewithin Athe bore I2g as the valvel approaches its seat |23. In thismanner, the valve will Permit th-e passage of less pressure fluid intothe opstanding column as the differential increases, and vice versa.

The diameter of the opening |52) through the valve member and the screwI6 ordinarily may be such as 1A; to --e inch, and, vcf course, may beThe greatest clearance between the valve member and the tapered'bore I2gis when the valve is widest open -as appears. This clearance at suchtime may be, for example, such as the equivalent of a circular openinghaving a diameter of 1/8 to 1% inch. When the valve is seated, the sideclearance between it and the tapered bore I2g may be such as two to fivethousandths inch.

The only valve seating -force for tubingL flow is exerted upon theexterior of the diaphragm by the pressure uid acting through theopeningi3d. This force is predetermined and constant at any given value of thepressure fluid.

The seating of the valve is resisted by the force required to flex thediaphragm, the force of the spring, and the presure of the upstandingcolumn. These are the only valve unseating forces. The force required toilex the diaphragm and spring is predetermined and constant; whereas,the upstanding column exerts the only variable force, the value of whichdepends upon the position in the upstanding column where it isexercised.

In both forms of the invention, the valves are normally supportedresiliently open until closed by the differential force.

The valves in both forms may be adjusted to close at progressively moreor less differential from the uppermost to the lowermost and to admit inthe same order or in reverse order,v progressively more or less pressurefluid as diilferent well conditions may require.

In flowing the wel] through the tubing, the path of the pressure uid outof the annular space Ia and into the tubing 2 is via the opening I3a,the passage |519, the annular space be'- tween the extension formed intothe valve I5a and the wall of the bore |2g, the chamber I2h, and theopenings I2e, in the order named.

The valve I 5a should be adjusted to close at a pressure per square inchsomewhat greater than the force per square inch exerted by the wellliquid between adjacent devices, Which'may be spaced 150 to 300 feetapart. In both forms of the invention, the valve should be so adjustedin order to provide for continuous even flow of well liquid through theeduction tube, which will result from two or more valves being open atonce.

The valve of the pressure fluid employed to iiow the well should be atleast two to three times the differential force required to close theValves, and may be much greater. Manifestly,

increasing the value of the pressure fluid Vwill in-` crease the rate ofliquid expulsion.

The diameter of the diaphragm, being man;7 times greater than thediameter of the valve, it is evident that comparatively great force willbe imparted to the valve, enabling it to be leakproof upon its seat.

It will be understood that expulsion of well liquid will be accomplishedby theA expansion of pressure uid injected int-o the upstanding columnthrough the devices herein shown.

During tubing flow, in Fig. 1 the discharge opening 4a in the casinghead will be considered as closed. The devices I2 are shown connectedinto the tubing 2 central of the well casing I, the casing head 4 beingemployed to effect a hermetic seal between the tubing and the casingproximately above the ground surface 8. Within the upper portion of thewell, the tubing may be enlarged for tubing flow, the two sizes beingjoined together by the swaged nipple 5. For casing flow, the tubing,which then becomes the induction tube, may be smaller and preferably allof one size. The flow line 2b, being an extension of the eduction tube2, will be considered as open and connected to a production tank.

The anchor string ,'I, connected to the eduction tube 2 by means of thenipple 6, having lateral CFI line 3 into the annular space Ia. Thevalves in all devices will be quickly closed by the excess pressureexterior of the diaphragm. The liquid in the casing will be depressed toa level shown at B, while the balancing upstanding column will rise toC.

The valve in the device next above the base of the upstanding columnwill open, while the next valve above will be closed by either slightpressure or will be partially open, according to the differentialobtaining there.

If the rate of liquid flow from the Well exceeds the rate of in-flow,the level B will be gradually lowered, uncovering the lower valves;While the upper valves will close, in turn, as the liquid level islowered within the annular space I a.

The construction shown in Figs. 4 and 5 is an adaptation to casing flowof the device shown in Figs. 2 and 3 for tubing ow.

The diaphragm and valve are reversed in position from that shown in Fig.3. The cap I9 intermediate of the guide ns I2C and having the openingsISU., is threadedly engaged within the boss I ZAd, and hermeticallyclamps the diaphragm upon the packing I8, thereby positioning Iing forceis exerted upon the diaphragm through the opening I2Ae; while theunseating force of the well liquid in the upstanding column acts throughthe openings IBa and the chamber I 9b upon the other side of thediaphragm by contacting the plate I5. This unseating force is aided bythe spring Il and the force required to flex the diaphragm, as wasstated for the tubing flow method.

In Fig. 5 the casing ow path of the pressure fluid is out of theinduction tube 2 via the opening I2Ae, the opening |51), the annularclearance between the tubular extension of the member I5 having its endformed into the valve I5a and the wall of the tapered bore I2g, thechamber IBb, and the openings I 9a, in the order named.

The installation plan in Fig. 1 will'be modified for ilowing through thecasing by replacing the larger size tubing and swaged nipple 5 withtubing of the smaller size shown below. The input pressure iluid line 3of the tubing flowvmethod Y will be replaced by a plug. Theeduction'tube discharge opening 4a. will be open, and the pressure fluidwill be supplied into the induction tube 2 through the line 2b. Theliquid level in both induction and eduction tubes will be assumed to beat A, Fig. 1.

openings 6a, may extend to the bottom of the Y 5, in all of the devices.

Now, to ilow the well through the annular space Ia, employing the casingas the eduction tube, turn pressure fluid from theY line 2b into thetubing 2 which pressure fluid will soon build up enough pressure toclose the valves I5a, Fig.

The liquid in the induction tube will be depressed t0 D, while theupstanding column in the eduction tube will rise and upstand from D toE.

The device next above the base of the upstanding column at I) will thenbe open, due to'the slight diierential obtaining therej While thedevicenext above it will remain closed by slight force or be partially open,as was explained for the tubing flow, to which this operation vofflowing through the casing is so similar as to be readily understoodwithout further explanation.'

Manifestly, the size of the openings thro-ugh which the pressure uidp-asses in its travel through the devices should vary according to thevolumetric flow and physical properties of the liquid, the depth of thewell, and the value of the pressure fluid.

The comparatively low starting pressures resulting from stage liftingand the metered flow of the power medium to the load, affords unusuallylow gas-liquid ratios and, at the same time, enables the well to producemore than the employment of higher pressures would permit.v It isobvious that many mechanical changes, substitutions, and adaptations maybe made' in the construction, and that equivalents maybe substituted forthe parts shown; and I reserve the right to make such mechanicalchanges, substitutions, and adaptations within the scope of theinvention as comprehended by the stated objects and appended claims.

What is claimed is:

1. A tubing coupling having a cylindrical chamber in the wall thereof,ports opening in- Wardly and outwardly from within said chamber to theinterior and exterior of the valve body, a tapered bore in the wall ofthe chamber opposite one of said ports, a diaphragm adjacent said lastmentioned port and having its periphery hermetically secured to thewalls of the chamber, a tubular valve passing through said diaphragm andterminating within said tapered bore to control the flow of uid as thevalve vmoves within the bore and to close the passage through thechamber when the valve seats Within the bore, and means resilientlyurging the valve outwardly from within said bore.

2. A tubular valve body having a chamber in the wall thereof with portsopening to the interior and exterior of the body, one of said portsopening centrally of the chamber, a tapered bore in the wall of thechamber opposite said last mentioned port and in alinement therewith, atubular valve extending inte said bore, the walls of said borecooperating with the surface of the valve to control the flow of uidthrough the valve, there being a valve seat at the inner end of the borefor engagement by the valve to close the passage therethrough and meansresiliently urging the valve away from said bore.

3. A valve body having a chamber in the Wall thereof with ports inwardlyand outwardly therefrom to the interior and exterior of the body, one ofsaid ports opening centrally of the chamber, a tapered bore in the wallopposite said last mentioned port and in alinement therewith, a valvemoveable in the chamber and having a portion extending into said bore, apassage in said valve terminating within said bore, the walls of saidbore cooperating with the surface of the valve to control the ow offluid through the valve, there being a valve seat at the inner end ofthe bore for engagement by the valve to close the passage therethrough,and means within said chamber resiliently urging the valve from withinsaid bore.

4. A valve body having a tubular boss thereon, a diaphragm, meanssecuring the periphery of said diaphragm to said boss and forming achamber therein, ports opening from said chamber to the interior of thevalve body, a tubular valve member secured to the diaphragm andextending into said chamber, a tapered bore in the Wall of the chamberreceiving the inner end of the valve member and forming a closure seatwhen the diaphragm is flexed by a differential pressure between theoutside and inside of the body, and means normally urging the valvemember resiliently outwardly.

5. A valve body having a tubular boss thereon, a shoulder within saidboss, a diaphragm, a cap member secured within the boss to clamp theperiphery of the diaphragm to the shoulder and form a chamber, a portopening from the interior of the body to the inner surface of saiddiaphragm, an inwardly opening tapered bore within the cap member, and atubular valve secured to the diaphragm and extending into said bore,there being openings through the cap member from within the chamber,whereby passage of pressure uid from the interior to the exterior of thebody is controlled in accordance with the differential pressuretherebetween.

6. A flow device for wells including a tubular valve body having aradial counterbore in the wall thereof, means closing said counterboreto form a chamber in the wall of the body, a diaphragm sealably.engaging the wall of the counterbore proximate one end of the chamber,a tubular valve member secured centrally of the diaphragm and providinga passage axially of the chamber, a tapered bore in the wall of thechamber into which said valve member extends, and means normally urgingthe valve outwardly from within said bore, there being passages fromythe interior of said chamber to the interior and exterior of the valvebody, whereby pressure fluid is admitted through said chamber and valvemember lby a predetermined diierential pressure between the interior andexterior of the valve body.

ALEXANDER BOYNTON.

